He "used magic because he was sad" anyway.
The existential impact on him from both things from both universes led to the same downward spiral. It wasn't him wrapping his entirety of meaning into not being able to doctor anymore because of his hands, it was him wrapping his entirety of meaning into her. He still lost something, and grief can lead you into weird places. I just figured he'd be looking into things more necromantic in this story than the dangerously preventative route it took.
I guess I just don't understand how "use magic to make my hands worky" is any less of a logic leap than "use magic to make my lover not dead".